While the traditional clinical trial design lays emphasis on testing the treatment effect between randomly assigned groups, it ignores the role of patient preference for a particular treatment in the trial. Yet, for healthcare providers who seek to optimize the patient‐centered treatment strategy, the evaluation of a patient's psychology toward each treatment could be a key consideration. The two‐stage randomized trial design allows researchers to test patient's preference and selection effects, in addition to the treatment effect. The current methodology for the two‐stage design is limited to continuous and binary outcomes; this article extends the model to include count outcomes. The test statistics for preference, selection, and treatment effects are derived. Closed‐form sample size formulae are presented for each effect. Simulations are presented to demonstrate the properties of the unstratified and stratified designs. Finally, we apply methods to the use of antimicrobials at the end of life to demonstrate the applicability of the methods.

中文翻译：

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两阶段随机试验设计，用于测试计数结果的治疗，偏爱和自我选择效果。

尽管传统的临床试验设计侧重于测试随机分配的组之间的治疗效果，但它忽略了患者对试验中特定治疗方法的偏爱。但是，对于寻求优化以患者为中心的治疗策略的医疗保健提供者来说，评估患者针对每种治疗方法的心理可能是一个重要的考虑因素。两阶段随机试验设计使研究人员除治疗效果外，还可以测试患者的偏好和选择效果。目前用于两阶段设计的方法仅限于连续和二进制结果。本文将模型扩展为包括计数结果。得出关于偏好，选择和治疗效果的测试统计信息。每种效果均采用封闭形式的样本量公式。进行仿真以证明未分层和分层设计的特性。最后，我们将生命周期结束时的方法应用于抗菌药物的使用，以证明该方法的适用性。